Uniting lacquered cellulose foils



' oi the gluing or connecting agent Patented Nov. 22, 1932 -1, s3s,4o2

RICHARD 'ETIEEEBI'G-A'Ul), OI' Bomm nm WALSBODE, GER-MARY Umrnm LAOQUEBED CELLULOSE FOUS Application !led July 9, 1980, Serial lo.

This invention has reference to adhesively connecting surfaces of different material to each other and in particular to the connection of superficially coated bodies and t s ntended to provide for a more reliable and secure connection of these exterior coatings to each other than nerally obtainable heretofore and toavod the se aration of the coatings from the coated sur aces and the destructon of the coatin and to generally obtain other important o 'ects and advantages which will appear as t e s ecifica'tion proceeds. The tearing strengt and resistance of the adhesive connection of two surface s governed by the reliability'of the' 'adheson aplied to the surfaces to be pasted to each ot er and generali anchored inthe capllary'walls of the sur aces,` and it further depends on the cohesion between the individual particles of the gluing or adhesive agent. The, stren h of connection obtained by the gluin toge er of the surfaces increases with the ormation of a egel, inasmuch as the gluing agent is retain on the capillary walls by adso'ption while the required gel-structure'is preserved by the forces of cohesio In order to provide for the entering of the adhesive agent into the pores of the surfaces'to be connected it should be adapted to wet these surfaces, inasmuch as it is well known that gelatine coats will break and come ofl' from surfaces of metal or hard rubber in view of the fact that these substances are not wetted b A aqueous solutions of gelatine, so that the a hesve intensit of 'these agents to ,the surfaces mention'e is very low. I

Still more complicated and uncontrollahle are the conditions for the connection by adhesives of surface coatings of varnish or the like to each other. In the case of em loying ad hesve agents for such coatings which possess arsufcent degree of adhesiv'eness and connectng property with relation to the outer surfaces to be directly connected 'ofthe coatings of varnsh, that is to say when employn g agentsof satisfactory wetting properties wth relaton to the surface mentoned and `adaptecl to be'adsorbed thereby and constitutng the requred gel-connection or 'bridge be- `which are not on 377.063, aid n Germany m s, aas.

tween the several parts of these layers there i is the cventuality that the relatiye cohesion ofthe particles of the gel and their' adheson to the particles of the surface coating of varnish is greatly in excess of the adheson of the layers of varnish to the bodies to be unted to each other. As a result thereof. the layers of varnish are likely to be ruptured and to scale oli from their supporting surfaces. This fact maybe 'shown or instance by an experiment in which a solution of latine is" allowed to dry up in an exteriorly g azed porcelain dish. The cohesion of the elatineparticles to 'each other and their ahesion with relation to the glazed exterior coating is. greater than the adhesion of the latter to the supporting surface of porcelain', so that the glazed coating will splnter and cone ofi in the form of small scale-Iike fragmente. It appears therefore that great di culties are presented b the problem of gluing heterogeneous bo ies to each other such as for instance un'ting paper to celluloid or uniting two bodies the surfaces of which are provided with coatin such as for instance with layers of varmsh or the like, and as additional instances in this connection reference may be made to the'unitin of foils orfilms or sheets of cellulose coate with solutions of cellulose esters. 4

These various dfliculties are obviated by the emplo ment of a. luingagent which is capable o wetting bot the'two surfaces of the coatings to be directly united as well as of wetting the bodies themselves underneath these lagers and which are to'be connected to each ot er, the new gluing agent presenting moreover a sufliciently large degree of adhesion and retaining action with relation to these coating layers and to the bodies themselves, so as to insure a reliable and efl'icient union of the bodies to each other. In put-suance of a series of experiments conducted with varnish coated bodies it has beemascertained that a highly satisfactory union of such bodies with an adhesive agent may be obtained by emploing agents of this kind y adapted to paste the layers of varnish to each other but also to extend their adhesive action through these layers and onto the surfaces it is' desired to connect to each other by the gluing operation. In conformity With these requirements my invention provides for the use of adhesive agents possessing a superior retaining and adhesive and sticking action both with relation to the layers of varnish coating as well with relation tothe supporting surfaces themselves combined with a certain amount of dissolving action for the varnish coating. By this means it becomes possible not only to firmly unite the layers of varnish coating to each other, but to exert a gluing action upon the su porting surfaces by the judicial selection o the glue, so as to avoid blistering and scaling ofl' of the layers of varnish coating, the union thus obtained reliably resisting separation for any len h of time. In case of surface coatings for the odies to be connected which consist of any other coating material but varnish,the gluing agent should be such that it produces a certain amount of dissolving action upon 'this coating material aside of the property of adhesion for the bodies and the surface coatings thereof.

The manner of action of the glue or pasting agent according to the invention is shown diagrammatically on the accompanying drawing in sectional View through fractions of the bodies to be united` If it is desired to paste the two bodies 1 and 1' to each other of which one is provided with a surface coating layer 2 and the other one with a surface coating layer 2', the gluing agent a inserted between the two la ers 2, 2' should possess the necessary adhesve action required for a reliable union of the coating la ers 2, 2', as well as for the bodies 1, 1', an in addition thereto it should present a certain 'amount of dissolving properties for the coating layers 2, 2'. If the bodies 1, 1' are constituted by sheets of cellulose upon which are disposed superficial layers of varnish consisting of cellulose esters, an adhesive compound should be employed which possesses a satisfactory degree of sticking and adhering properties with relation to the cellulose sheets and the layers of cellulose esters in addition to a certain amount of dissolving action with relation to the varnish coating of cellulose esters. Thus I may use as an instance for the union of two sheets or films of glassy viscose coated with a varnish of nitrocellulose, a gluing compound which contains 10 percent of gum arabic and 40% of sugar and containing an admixture of 50 cc. of acetaldehyde for each 60 grams of this mixture, the remainin percents of the mixture bein water. In e case of sheets or films of vscose eoated with acetyl-cellulose the pasting agent may for instance consist of 20 perce't gelatine, 15 percent glycerine with an addition of 50 cc. acetone for each 60 grams of this compound the balance of this mixture bein water. tone and acetalde yde I may also use as additions lactic acid, acetic acid or other suitable solvents which produce a kind of swelling action upon the coating layers of the cellulose body. Instead of gelatine, of gum arabic and sugar I may also use other suitable gluing agents, and the proportions of the difl'erent ingredients of the gluing compound may be suitably selected and ad- 'justed in accordance with the requirements of the particular case.

When it is desired to unite bodies 'of other material but cellulose and in the case of coating layers consisting of other agents different from cellulose-ester-Varnishes, the pasting or gluing agent may possibly have to be produced from other ngredients, provided the composition obtained as regards its adhering and sticking properties for the bodies to be united and for the coating la ers and as regards dissolving properties or the coating material will correspond to the re uirements of this invention. It should also e pointed out in this connection that the invention is not limited to certain specific proportions of the various ingredients, the amount of which will be governed by the materials under consideration and by the convenience of the user and in accordance with the scope of the appended claims.

I claim 1. In a method of eementing together cellulose foils capable of swelling in water and provided with a lacquer coating, with their lacquered surfaces juxtaposed, the employment as hesive of a mixture of a gluing agent an of an Organic acid selected from the group containing lactic and acetic acid.

2. A composite sheet composed of two cellulose sheets capable of swelling in water, two juxtaposed lacquer coatings applied to said cellulose sheets and an intermediate layer consisting of a mixture of a gluing agent having good adhesive properties both for the coatings and for the cellulose sheets and of a solvent for the lacquer coatings.

3. A composite sheet composed of two eellulose sheets capable of swclling inwater, two juxtaposed lacquer coatingsapplied to said cellulose sheets and an intermediate layer consisting of a gluing agent and of an Organic acid selected from the group containing lactic acid and acetic acid.

4. A method of cementing together cellulose foils capable of swelling in water and provided with a lacquer coating, with their lacquered surfaces juxtaposed which comprises the employment as adhesive of a mixture of gum arabic and sugar and of acetaldehyde. 4

5. In a method of gluing' together cellulose foils provided with a lacquer coating, with their lacquered surfaces juxtaposed, the

Instead of aceemplo ment as adhesive of a mi xtre of gel'atine, ycerine and acetone. i

6. i composite sheet composed of two cellulose sheets capable of swelling in water, two juxtaposed lacquer coatings applied to J said cellulose sheets and an intermediate layer consisting of an adhesive containing gum arabic and sugar and acetaldehyde.

7 A composite sheet com osed of two cellulose sheets capable of swe ing in water, two juxtaposed lacquer coatings applied to said cellulose sheets and an intermediate layer eonsisting ,of a mixture of 'gelatine, glycerine and acetone.

In testimony whereof I aflix my signature.

RICHARD WEINGAUD.

ERTIFICATE OF CORRECTION.

Ptent No. 1,888.402. November 22, 1932.

It is hereby Certified that the name of the inventor in the above iubered 4 patent was erroneously written and printed as "Richard Weingad" whereas said ne should h've been written and printed s"Richard Weinganl"; and that the seid Letters Potent should he rend with this cor 'ection therei that the same may confor to the record of. the case in the Ptent Office.

Signed' d eled this 7th dy of February. A. D. 1933.

M. J. 0 3119 (Seul) Acting onmissione' of Patents.

` emplo ment as adhesive of a mi xtre of gel'atine, ycerine and acetone. i

6. i composite sheet composed of two cellulose sheets capable of swelling in water, two juxtaposed lacquer coatings applied to J said cellulose sheets and an intermediate layer consisting of an adhesive containing gum arabic and sugar and acetaldehyde.

7 A composite sheet com osed of two cellulose sheets capable of swe ing in water, two juxtaposed lacquer coatings applied to said cellulose sheets and an intermediate layer eonsisting ,of a mixture of 'gelatine, glycerine and acetone.

In testimony whereof I aflix my signature.

RICHARD WEINGAUD.

ERTIFICATE OF CORRECTION.

Ptent No. 1,888.402. November 22, 1932.

It is hereby Certified that the name of the inventor in the above iubered 4 patent was erroneously written and printed as "Richard Weingad" whereas said ne should h've been written and printed s"Richard Weinganl"; and that the seid Letters Potent should he rend with this cor 'ection therei that the same may confor to the record of. the case in the Ptent Office.

Signed' d eled this 7th dy of February. A. D. 1933.

M. J. 0 3119 (Seul) Acting onmissione' of Patents. 

